Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversit...Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversity. The river-lake relationship between Mekong River and Tonle Sap Lake is unique and has always been a major focus in the international community. The land terrain and under-water topography were used to analyze the morphological characteristics of Cambodia Mekong Delta and Tonle Sap Lake. Long series of hydrological data of river-lake controlling stations were used to analyze the water level variation characteristics and water volume exchange pattern between Mekong River and Tonle Sap Lake, and the response relationship to river-lake morphological characteristics were also researched. The results show that: Cambodia Mekong Delta and Tonle Sap Lake Area is low-lying and flat with gentle channel gradient and water surface gradient, making the relationship between water level and area (or volume) smooth. The channel storage capacity of Mekong River and Tonle Sap River is not enough compared to the inflow, so vast flooding plain is extremely prone to be inundated, making the flood relationships between the left and right banks become very complicated. Tonle Sap Lake is a seasonal freshwater lake with water flowing in and flowing out, and the timing and intensity of water exchange with Mekong River are closely related to the water flow resistance at the exit section of Tonle Sap Lake and the cross-sectional area of Tonle Sap River, which can be reflected by the river-lake water level difference and the water level of Tonle Sap River. Affected by the river-lake morphological characteristics, the water exchange intensity between Mekong River and Tonle Sap Lake is great. Tonle Sap Lake not only stores 14.4% of flood volume (39.7 billion m3) from the Mekong River every year, but also supplies 29.7% of dry water (69.4 billion m3) to the Mekong River. Influenced by the adjustment of the floodplain, the water level fluctuation of Mekong River and Tonle Sap Lake is slow, and the rising and droop rates of water level are positively correlated with the floodplain storage area. The research results will help to understand the relationship mechanism between Mekong River and Tonle Sap Lake and provide a scientific basis for the comprehensive governance of Cambodia Mekong Delta and Tonle Sap Lake Area.展开更多
The waste water system generated in the process of production of cuprous chloride was studied.The existing forms of copper in the system and the influence of temperature and pH on the existing forms of copper ion were...The waste water system generated in the process of production of cuprous chloride was studied.The existing forms of copper in the system and the influence of temperature and pH on the existing forms of copper ion were analyzed and determined through calculating the coefficients of copper complex distribution.In the waste water system,the main forms of copper are CuSO4, Cu2 +,CuCl + ,CuCl, 2-and2- 3 CuCl.Temperature has little influence on the distribution coefficient of Cu(Ⅱ),but has significant influence on distribution coefficient of Cu(Ⅰ).With the increase of temperature,the distribution coefficient ofCuCl, 2-increases significantly while the distribution coefficient of2- 3 CuCl decreases.The pH has nearly no influence on the distribution coefficients of various Cu(Ⅰ)-compounds,but has sizable influence on the distribution coefficients of Cu(Ⅱ)-compounds.With the increase of pH,the distribution coefficient of CuSO4(aq)increases while the distribution coefficients of Cu 2+ and CuCl + decrease.According to these results,the anion resin of 201×7 OH-and the cation resin of 732 Na were chosen to dispose the waste water solution of cuprous chloride.Finally,97.9%copper in the waste water is recovered.展开更多
By using field-survey hydrological data of the related control stations in Dongting Lake and the Yangtze River mainstream in 1951-2010, the evolution characters of water exchange abilities between the two. water bodie...By using field-survey hydrological data of the related control stations in Dongting Lake and the Yangtze River mainstream in 1951-2010, the evolution characters of water exchange abilities between the two. water bodies and their response to the operation of the Three Gorges Reservoir （TGR） from different time scales are analyzed based on their hydraulic relations. The results are shown as follows. Firstly, during July-September, the replenishment ability of Three Outlets to Dongting Lake is stronger, and in January-March, the replenishment ability of Dongting Lake to Yangtze River is stronger. Secondly, there has been an obvious inter-decadal wave on the water exchange coefficient between Dongting Lake and Yangtze River. In 1951-1958 and 1959-1968, the replenishment ability of Three Outlets to Dongting Lake was stronger, but in 2003-2010, the replenishment ability of Dongting Lake to Yangtze River has been strengthened. Thirdly, the spill-division ability of Three Outlets weakens, and the water of Dongting Lake coming from Three Outlets decreases either in typical years or under different dispatching modes of the TGR after the operation of the Three Gorges Reservoir. Furthermore, the water of Dongting Lake coming from Four Rivers takes the dominant position, which obviously enhances the replenishment ability of Dongting Lake to Yangtze River. Fourthly, if the effect of the runoff fluctuation in the basin is not considered, the evolution characters of the exchange capacities and the exchange process between Dongting Lake and Yangtze River in different time scales are generally changed with the variation of the water exchange amount between them, although the factors influencing the water exchange capacities between them is very complex. These show that there is an in-line growth or decline relation between the river-lake water exchange ability and the river-lake water exchange amount.展开更多
文摘Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversity. The river-lake relationship between Mekong River and Tonle Sap Lake is unique and has always been a major focus in the international community. The land terrain and under-water topography were used to analyze the morphological characteristics of Cambodia Mekong Delta and Tonle Sap Lake. Long series of hydrological data of river-lake controlling stations were used to analyze the water level variation characteristics and water volume exchange pattern between Mekong River and Tonle Sap Lake, and the response relationship to river-lake morphological characteristics were also researched. The results show that: Cambodia Mekong Delta and Tonle Sap Lake Area is low-lying and flat with gentle channel gradient and water surface gradient, making the relationship between water level and area (or volume) smooth. The channel storage capacity of Mekong River and Tonle Sap River is not enough compared to the inflow, so vast flooding plain is extremely prone to be inundated, making the flood relationships between the left and right banks become very complicated. Tonle Sap Lake is a seasonal freshwater lake with water flowing in and flowing out, and the timing and intensity of water exchange with Mekong River are closely related to the water flow resistance at the exit section of Tonle Sap Lake and the cross-sectional area of Tonle Sap River, which can be reflected by the river-lake water level difference and the water level of Tonle Sap River. Affected by the river-lake morphological characteristics, the water exchange intensity between Mekong River and Tonle Sap Lake is great. Tonle Sap Lake not only stores 14.4% of flood volume (39.7 billion m3) from the Mekong River every year, but also supplies 29.7% of dry water (69.4 billion m3) to the Mekong River. Influenced by the adjustment of the floodplain, the water level fluctuation of Mekong River and Tonle Sap Lake is slow, and the rising and droop rates of water level are positively correlated with the floodplain storage area. The research results will help to understand the relationship mechanism between Mekong River and Tonle Sap Lake and provide a scientific basis for the comprehensive governance of Cambodia Mekong Delta and Tonle Sap Lake Area.
基金Projects(5087408750978212)supported by the National Natural Science Foundation of China+1 种基金Project(2006E106)supported by Natural Science Foundation of Shaanxi Province,ChinaProject(07JK302)supported by Special Natural Science Foundation of Shaanxi Province Education Office,China
文摘The waste water system generated in the process of production of cuprous chloride was studied.The existing forms of copper in the system and the influence of temperature and pH on the existing forms of copper ion were analyzed and determined through calculating the coefficients of copper complex distribution.In the waste water system,the main forms of copper are CuSO4, Cu2 +,CuCl + ,CuCl, 2-and2- 3 CuCl.Temperature has little influence on the distribution coefficient of Cu(Ⅱ),but has significant influence on distribution coefficient of Cu(Ⅰ).With the increase of temperature,the distribution coefficient ofCuCl, 2-increases significantly while the distribution coefficient of2- 3 CuCl decreases.The pH has nearly no influence on the distribution coefficients of various Cu(Ⅰ)-compounds,but has sizable influence on the distribution coefficients of Cu(Ⅱ)-compounds.With the increase of pH,the distribution coefficient of CuSO4(aq)increases while the distribution coefficients of Cu 2+ and CuCl + decrease.According to these results,the anion resin of 201×7 OH-and the cation resin of 732 Na were chosen to dispose the waste water solution of cuprous chloride.Finally,97.9%copper in the waste water is recovered.
基金National Natural Science Foundation of China, No.41071067 Construct Program of the Key Discipline of the Physical Geography in Hunan Province
文摘By using field-survey hydrological data of the related control stations in Dongting Lake and the Yangtze River mainstream in 1951-2010, the evolution characters of water exchange abilities between the two. water bodies and their response to the operation of the Three Gorges Reservoir （TGR） from different time scales are analyzed based on their hydraulic relations. The results are shown as follows. Firstly, during July-September, the replenishment ability of Three Outlets to Dongting Lake is stronger, and in January-March, the replenishment ability of Dongting Lake to Yangtze River is stronger. Secondly, there has been an obvious inter-decadal wave on the water exchange coefficient between Dongting Lake and Yangtze River. In 1951-1958 and 1959-1968, the replenishment ability of Three Outlets to Dongting Lake was stronger, but in 2003-2010, the replenishment ability of Dongting Lake to Yangtze River has been strengthened. Thirdly, the spill-division ability of Three Outlets weakens, and the water of Dongting Lake coming from Three Outlets decreases either in typical years or under different dispatching modes of the TGR after the operation of the Three Gorges Reservoir. Furthermore, the water of Dongting Lake coming from Four Rivers takes the dominant position, which obviously enhances the replenishment ability of Dongting Lake to Yangtze River. Fourthly, if the effect of the runoff fluctuation in the basin is not considered, the evolution characters of the exchange capacities and the exchange process between Dongting Lake and Yangtze River in different time scales are generally changed with the variation of the water exchange amount between them, although the factors influencing the water exchange capacities between them is very complex. These show that there is an in-line growth or decline relation between the river-lake water exchange ability and the river-lake water exchange amount.
